Circuits often include numerous active devices and passive devices electrically connected together. In some instances, active devices include multiple fingers. Fingers help to spread a current through a device over multiple sub-devices. In an example of a metal oxide semiconductor (MOS) transistor, each sub-device includes a source, a drain and a gate. The gate of the sub-device is called a finger. In some approaches, fingers for each device are grouped together in close proximity to each other in order to reduce a complexity of electrical connections between the various sub-devices.
During operation of a circuit, certain devices have a higher power density than other devices. Resistance within devices results in production of heat as a current passes through the device. As the power density of a device increases, resistance within the device causes an increase in a temperature rise of the circuit around the device. In addition, as node sizes decrease, planar transistors are being converted to three-dimensional channel transistors in order to save space within the circuit. These three-dimensional channel transistors have reduced heat dissipation capacity in comparison with planar transistors.